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StatisticsQ&A LibraryFlashlight Battery Lifetimes. A brand of ashlight battery has normally distributed lifetimes with a mean of 30 hours and a standard deviation of 5 hours. A supermarket purchases 500 of these batteries from the manufacturer. What is the probability that at least 80% of them will last longer than 25 hours?Start your trial now! First week only $4.99!*arrow_forward*

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**Flashlight Battery Lifetimes.** A brand of ashlight battery has normally distributed lifetimes with a mean of 30 hours and a standard deviation of 5 hours. A supermarket purchases 500 of these batteries from the manufacturer. What is the probability that at least 80% of them will last longer than 25 hours?

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